The invention relates to a vegetation element.
Vegetation elements are being produced to an increasing extent, and a preferred application consists of using them for sodding on flat or inclined roofs of both residential houses and industrial buildings.
The vegetation elements can be precultivated outside of their subsequent site of use before being laid on a roof subsequently. To this end, the vegetation carriers are laid as mat sheeting on a substrate, and seed is applied to the vegetation body. Then it is precultivated with horticultural care until the vegetation bodies have been sodded and are available as a finished vegetation element. The vegetation elements can then be rolled up into rolls and conveyed to a roof where they are then unrolled. To achieve a more reliable handling of these prefabricated vegetation elements, they usually have a water-permeable carrier layer of a nonwoven or a coarse mesh fabric on the bottom side of the vegetation carrier. Such a vegetation element is known from European Patent Application EP 706,753 A1, where the vegetation carrier is made of a mineral material in the form of a hygroscopic rock wool mat.
In addition, however, it is also possible to sod roofs directly on site and install the vegetation body directly on the roof, where in this case the bottom carrier layer mentioned above may be omitted. Seeds are again sown on the vegetation carrier, and after a certain growth period, the finished sodded vegetation element is created on the roof. In precultivation and in direct on-site sodding with these vegetation elements, seeds must be sown on the vegetation body. In practice, these seeds are applied manually by a person. It is often observed that the seeds are distributed very unevenly on the vegetation body, so there are some areas with too many seeds and other areas with very few seeds or even empty spaces where there are no seeds. This leads to uneven sodding of the vegetation element, which is a disadvantage.
When the person who sowed the seeds notices that they are not distributed evenly, that person will try to fill the empty spaces or fill up the sparsely seeded areas by applying more seeds. However, this leads to the result that more seeds are applied on the whole than would actually have been necessary for the given area of the vegetation element. Consequently, the cost of producing the vegetation elements is increased.
The object of this invention is to create a vegetation element that has uniform sodding and costs less to produce, regardless of whether the vegetation element is produced in the sense of precultivation or direct on-site sodding, and also regardless of which type of known vegetation elements is used, in other words, regardless of whether the vegetation element consists of several layers.
The basic idea of the invention consists of using a seed mat of flexible, biodegradable material. This seed mat contains individual seeds that are spaced a distance apart and are secured at certain separate locations through the seed mat and held in place there. The seed mat thus already has the seeds required for sodding, which have been arranged uniformly in advance in or on the seed mat.
Instead of sowing the seeds as before, the invention proposes that the vegetation carrier be provided with a seed mat having seeds. The known sowing of seeds is thus replaced by applying the seed mat.
Since the seeds are already distributed evenly, this also yields uniform sodding for the vegetation element in an advantageous manner. In experiments, it has been found that seed consumption can be reduced by more than 50% with this invention.
This invention can be used with precultivated vegetation elements having a bottom carrier layer as well as with vegetation elements where the vegetation carrier is installed directly on the roof, etc. In each of these cases, the process of sowing seeds is replaced by the application of a seed mat.
According to an expedient embodiment of the invention, the seed mat consists of a bottom layer and a top layer connected to it, between which the seeds are secured, and the bottom layer and the top layer are made of a nonwoven. The individual layers may be very thin and designed so that the eye can see the seeds between them and their uniform distribution.
Another expedient embodiment of the invention consists of the fact that the top layer of the seed mat is formed by an adhesive layer of a plant-compatible adhesive. Thus, in this case the seed mat consists of a bottom layer on which the seeds are distributed. Then the adhesive layer is applied as the top layer, securing the seeds and holding them in place.
According to another preferred embodiment, the seed mat comprises a bottom nonwoven carrier on which the seeds are arranged. The nonwoven carrier is then sprayed with a plant-compatible adhesive, so the seeds are secured and held in place on the nonwoven carrier.
The seed mat is arranged on top of the vegetation carrier in an expedient manner and connected to the vegetation carrier, where it is advantageous to mechanically attach the seed mat to the vegetation carrier. Joining with threads in the form of chain warp stitches, for example, is suitable for this purpose.
However, the seed mat may also be glued to the vegetation carrier with a plant-compatible adhesive in an advantageous manner.
Attaching the seed mat to the vegetation carrier eliminates the risk of the seed mat being lifted away from the vegetation body by wind, for example. High wind forces can occur especially on high roofs.
Another expedient embodiment of the invention consists of performing or supporting the attachment of the seed mat to the vegetation carrier by applying a surface load to the seed mat, by applying gravel or coarse sand/stone chips to the seed mat as an air-permeable layer.
Another expedient embodiment of the invention provides for the seed mat to be arranged on the bottom side of the vegetation carrier. This variant also yields uniform sodding of the vegetation element, where the plants grow upward through the vegetation carrier.
In another embodiment of the invention, the seed mat can be arranged not only above or below but also inside the vegetation carrier. It is advantageous to make the vegetation carrier of two separate layers with the seed mat sandwiched between them.
In an advantageous manner, the seed may also contain a uniformly distributed fertilizer in addition to the seeds, to accelerate the plant growth process.
The invention also consists of using a seed mat made of a flexible, biodegradable material provided with seeds secured and held in place at certain locations as a measure to provide the required seeds for the vegetation carrier of a vegetation element for sodding artificial surfaces (such as roofs) or natural soil surfaces.
It should be pointed out that seed mats for use in the field of horticulture are essentially known. However, these have been limited to simply laying small seed mats on natural garden soil. No large area applications of the seed mat was known, nor could any have been carried out, because of the lack of means for securing the seed mats on the garden soil surface, and seed mats have not yet been used at all with vegetation elements laid in sheets over very large areas.